Capacitance loading question

[jdandy]

I have a question on capacitance loading on moving magnet phono cartridges. Does the capacitance value of the phono cable get added to the capacitance set in a phono stage preamp when setting up the cartridge loading? As an example, if the manufacture say 150 to 300 pFd, and the phono cables have a capacitance of 200 pFd, would I set the phono stage setting at 100 pFd to achieve a 300 pFd load?

[jwhite613]

Hi Dan. I can give you an example. When I bought my c2300 I called VPI to answer this for myself. I have the Ortofon Bronze (150-300 pfd) they told me to set my c2300 to 450pdf. Table VPI Classic. I think I remember him mentioning the pdf of the tonearm cable. Sorry I can't help more I can't remember his whole explanation but I did write down the setting.

[gtubes]

From my ASR manual below (this sounds like the capacitance value of the phono cable is subtracted, not added?)

You can easily determine the value for your cartridge by using the cartridge manufacturer’s
recommended value and subtract the capacity of the phono cable you are going to use –
the result is the value you have to adjust in your ASR Mini Basis.

[jdandy]

Originally Posted by mc602

From my ASR manual below (this sounds like the capacitance value of the phono cable is subtracted, not added?)

You can easily determine the value for your cartridge by using the cartridge manufacturer’s
recommended value and subtract the capacity of the phono cable you are going to use –
the result is the value you have to adjust in your ASR Mini Basis.

Greg.......That statement certainly makes it appear that the phono cable capacitance is subtracted.

I am using Wireworld 6.0 unbalanced one meter Silver Eclipse cables on my Micro Seiki to the C1000P. Wireworld told me the capacitance on one meter Silver Eclipse is 300 pf. Using the information you provided, I would have to set the C1000P loading to 500 pFd to load the Ortofon 2M Black with the recommended 200 pf of capacitance.

I'll give this a try, but I am still not confident this is correct. If anyone else has additional information please chime in.

[gtubes]

Dan, I'm not confident either. I get stuck on the math personally. And this manual is tricky at times, interpreting some of the explanations....

Where's Stephen or Alberto !

[Removed]

Dan.......The higher the capacitive value of the input of the phono stage the duller the sound will be.......The lower the capacitance of the phono input the brighter the sound gets. A mismatch results either in dark dull sound or a bright sound.

The capacitance of the phono cable should be taken into account when matching a moving magnet cartridge to the phono stage as the capacitance of the cable adds to the capacitance of the phono input.

[jdandy]

Originally Posted by A/V Solutions

Dan.......The higher the capacitive value of the input of the phono stage the duller the sound will be.......The lower the capacitance of the phono input the brighter the sound gets. A mismatch results either in dark dull sound or a bright sound.

The capacitance of the phono cable should be taken into account when matching a moving magnet cartridge to the phono stage as the capacitance of the cable adds to the capacitance of the phono input.

Jeff.......Thank you. That's what I thought, but I wasn't sure. Capacitance is cumulative. I had my C1000P set to 250 pf, and playback was sounding rather bright. Ortofon recommends 150 to 300 pf capacitance loading, so adding the 300 pf of my interconnects to the 250 pf added to the phono stage had me at 550 pf. I lowered the phono stage loading to 50 pf, as low as it would allow, and the cartridge sound smoothed out considerably.

I think I still need to play with the vertical tracking angle a bit. As I understand it, the Shibata tip is fairly sensitive to stylus rake, so the VTA needs to be adjusted accurately to satisfy the stylus angle for proper contact with the groove walls.

[Removed]

Originally Posted by jdandy

Jeff.......Thank you. That's what I thought, but I wasn't sure. Capacitance is cumulative. I had my C1000P set to 250 pf, and playback was sounding rather bright. Ortofon recommends 150 to 300 pf capacitance loading, so adding the 300 pf of my interconnects to the 250 pf added to the phono stage had me at 550 pf. I lowered the phono stage loading to 50 pf, as low as it would allow, and the cartridge sound smoothed out considerably.

I think I still need to play with the vertical tracking angle a bit. As I understand it, the Shibata tip is fairly sensitive to stylus rake, so the VTA needs to be adjusted accurately to satisfy the stylus angle for proper contact with the groove walls.

Dan......your on the right track now

I use a USB microscope for SRA....I try to hit the 90-92 degree mark, remember to set VTF every time you change VTA, run your black right at the 1.7 mark it likes to be on the heavy side at least this is what I have found.

[jdandy]

Originally Posted by A/V Solutions

Dan......your on the right track now

I use a USB microscope for SRA....I try to hit the 90-92 degree mark, remember to set VTF every time you change VTA, run your black right at the 1.7 mark it likes to be on the heavy side at least this is what I have found.

Jeff.......I sure appreciate your help. Thank you.

[Puma Cat]

Originally Posted by A/V Solutions

Dan......your on the right track now

I use a USB microscope for SRA....I try to hit the 90-92 degree mark, remember to set VTF every time you change VTA, run your black right at the 1.7 mark it likes to be on the heavy side at least this is what I have found.

Jeff: Where do you get this USB microscope and how do you use it measure SRA? Can you actually measure the difference between 90 and 92 deg with it with accuracy and precision or is this just a visual estimate?